Radios are traditionally based on super-heterodyne architecture. The super-heterodyne architecture, however, is complex and is only amenable to one small band of frequencies at a time, e.g., a spectral window. The complexity is due in part to the addition of mixers and various operational frequencies along with the inclusion of filters to suppress unwanted signals outside the desired spectral window. While conventional radios work well and provide robust communication systems, the ability to use a single radio for wider bands and to reduce the complexity of radios is highly desirable.
The desire for replacement radios that meet the goals of complexity reduction and high bandwidth has led to direct-sampling, wide band radios. The development of the direct-sampling, wide band radios has been predicated on the advances in analog-to-digital converter technology, as well as digital-to-analog converters. These radios, however, suffer when in-band strong signals drown out the weaker signals, which reduces the dynamic range of the radio, and have only operated as desired in controlled environments. Additionally, very high speed analog-to-digital converters have limited precision (8 to 10 bits), which suffices for strong signals, but hinders the detection and sampling of weak signals in the presence of strong signals.